/Engine/Source/Runtime/Engine/Classes/Engine/Texture2D.h
Calculates and returns the corresponding ResourceMem parameters for this texture.
true if the texture should use a ResourceMem. If false, none of the out parameters will be filled in.
bool GetResourceMemSettings ( int32 FirstMipIdx, int32 & OutSizeX, int32 & OutSizeY, int32 & OutNumMips, uint32 & OutTexCreateFlags )